Childhood autism is invariably accompanied by severe and widespread language deficits. Although about half of all children with this diagnosis eventually learn to speak, recent studies have shown that these children remain impaired relative to aphasic and younger normal children in their ability to use language appropriately for purposes of communication. In particular, they are more likely to produce inadequate responses or fail to respond at all to another person's questions and comments. It has also been observed that the language behavior of individual autistic children is not always deviant, an important consideration from the standpoint of intervention. However, the reasons for this within-child variability are not well understood. Therefore, one aim of the proposed study is to investigate whether particular features of a discourse setting can be identified which reliably predict the occurrence of appropriate language behavior for each of 15 verbal autistic children as they interact with a familiar adult. These features include particular characteristics of the adult's eliciting utterance, such as its conceptual and syntactic complexity, the type of response it calls for, and how it relates to previous discourse, as well as the child's response "set" at the time an utterance is addressed to him/her. These data will serve as the basis for a second phase of the proposed research, aimed at intervention. In this second phase, the adults who participated in the initial conversations will receive programmatic instructions concerning how to modify their conversational behavior in line with the particular features associated with adequate responding for a given child. The efficacy of this approach will then be evaluated by comparing pre- and post-intervention conversational data for each dyad.